In fact, the violence is quite strong, and there are several minor swear words as well. I wouldn't recommend this book to readers younger than thirteen years old. Stephen does a great job balancing his edgy content and a Christian worldview, which is still relevant in the context of an alien invasion.
So, let's get to it. The story: Earth has been invaded by not one, but three alien species of varying intelligence and battle capabilities. Scott Remington and a colorful crew of new recruits are thrown into the thick of things very quickly and manage to pull off impossible successes, much to the surprise (and sometimes envy) of their COs and fellow soldiers. Since this is only the first book in the Epic series, there are plenty of questions left unanswered but that's to be expected. The story is brisk, the action explosive, and the banter back at base is snippy and sarcastic.
I did think that plot felt a bit episodic - on-base training, battle, back to base, recuperate, train, battle, etc. Stephen follows a very realistic battle scenario, reminding me of the recent movie Battlefield: Los Angeles. Stephen could have removed the aliens and made his antagonists human invaders and the story would have worked equally well. This realism keeps the book grounded even when things become a bit far-fetched (but hey, this is entertainment, right?).
The characters are a mixed bag. Some are well-developed, some are cannon fodder. The female characters were a bit weak, in my opinion. They hardly see combat and exist mostly to tend to the men's wounds and fall in love with them. I don't like the modern trend of having every girl in an action story be a butt-kicking beauty, but in a story of impossibly awesome male characters, it would have been nice to see some impossibly awesome females as well.
The Christian elements were very thought-provoking, grappling with God's calling in one's life. The conflict in the protagonist's heart, and in the heart of his fiance, felt very real and easy to relate to. Everyone feels doubt in their own lives, but the stakes are higher when the wrong choice can mean death or losing the love of your life.
Dawn of Destiny draws heavily from Robert Heinlein's sci-fi classic Starship Troopers, but it stands on its own. If you're looking for a book series with hard-hitting action that isn't buried under a mountain of foul language and lewdness, the Epic Series should give you hours of enjoyment. And it's not finished yet!